NOVA chronicles the story of the space shuttle program and reveals what led to the 1986 Challenger and 2003 Columbia disasters.

The program:

explains that when President Richard Nixon cancelled the construction of a space station, the shuttle went from serving as a transport vehicle to operating as a platform for low-Earth orbit missions.

notes that in order to be cost effective, the shuttle increased its launches by taking on military and commercial payloads.

reports that the number of missions increased in the 1980s until the Challenger disaster on January 28, 1986; when missions resumed in 1988, they were all scientific.

points out that after the shuttle's maintenance was turned over to a private contractor in 1996, the shuttle's workforce was cut nearly in half.

chronicles the events leading up to the cause of the 2003 Columbia disintegration—pieces of foam that fell off the external fuel tank damaged the leading edge of the shuttle's wing.

recounts the flight crew's final moments in the February 1, 2003 disaster.

details the accident investigation board's analysis of the event and chronicles the board's findings, including the conclusive test board members conducted to verify that the foam was responsible for the shuttle damage.

reports on the board's findings in 2003 that led to a new vision for space exploration.

relates President George W. Bush's 2004 announcement regarding retiring the shuttle and calling for construction of a new spacecraft that would operate beyond low-Earth orbit.

presents features and safeguards of the new spacecraft, which will be part of the Constellation program.

notes improvements made in the current shuttle to increase its safety prior to its retirement.

Taping Rights: Can be used up to one year after program is recorded off the air.